Means and method for indicating weight and moisture variations in paper machines andthe like



1,93225 WEIGHT AND MOISTURE IKE 3 Sheets-Sheet '1 9 1933 A. EBROUGHTON MEANS AND METHOD FOR INDICATING VARIATIONS IN PAPER MACHINES AND THE L Filed April 7, 1950 awn 1:04;

Nave 211, 1933; A E BRQUGHTON 1936,25

MEANS AND METHOD FOR INDICATING WEIGHT AND MOISTURE VARIATIONS IN PAPER MACHINES AND THE LIKE Filed April 7, 1930 5 Sheets-Sheet 2 gwlnntoz Patented Nov. 21, 1933 PATENT OFFICE MEANS AND METHOD FOR INDICATING WEIGHT AND MOISTURE VARIATIONS IN PAPER MACHINES AND THE LIKE Arthur E. Broughton, Minneapolis, Minn.

Application April 7, 1930. Serial No. 442,268

7 Claims.

In the manufacture of paper the importance of uniformity in the weight and moisture content of the sheet has long been recognized because the product is purchased on a weight basis and with a specified moisture content. Heretofore it has been common practice, on account of unavoidable variations in these essentials, to reduce the moisture content below specifications with resulting loss to the manufacturer.

It is an object of this invention to provide enicient means associated with the paper drier and with a heat control therefor to facilitate the manual compensation,:or effect automatic compensation, for relatively small variations in the moisture content of the sheet at a selected point near the wet'end of the paper drier. A further object is to provide a thermostatic control element located near the wet end of a paper drier to regulate the weight or consistency of the stock or stuff supplied to the paper machine.

In carrying out my invention, I divide the drier into separately controlled sections (which, for convenience, are called the first and second sections) and place a thermostatic indicator or control device in contact with the partially heated paper web between these two sections. The moisture content is regulated by appropriate changes in the heat supplied to the second section in response to the indications, while a substantially constant or uniform heat is maintained in the first section. Where the consistency or weight is to be regulated further, the consistency of the stock supplied to the Fourdrinier or cylinder machine is changed from time to time in response to the indicator or temperature control element between dried sections. It will be understood that as the paper web passes from" one drying element or roll of the drier to another near the wet end of the machine the temperature of the sheet is progressively raised so that it may be said that the machine has a rising temperature curve at this end of the machine. In many driers, after the temperature of the sheet is raised to about 170 Fahrenheit (by the drying elements near the wet end), approximately this temperature is retained during the passage of the sheet over the subsequent heating elements. I place the thermostatic controlling element at a suitable point on the abruptly rising portion of the temperature curve and then vary the heat supplied to the drying elements corresponding to portions of the curve above the control element while maintaining a substantially constant heat supply for the drying elements corresponding to portions of the curve below the controlling element. I have discovered that the temperature of the web at a control element so located varies approximately in inverse proportion to the changes or variations in moisture content and consistency or weight of the stock.

That is, increased moisture content or increased thickness of the web produce lower temperatures, and reduced moisture or thickness produces higher temperatures at such control element.

In the accompanying drawings suitable apparatus for carrying out my invention in connection with a paper drier of common type is shown. In the drawings, Figure 1 is a side elevation of the control end of the device, and showing diagrammatically suitable electric signal and control circuits, certain parts being shown in vertical section, for clearness; Fig. 2 is a side elevation indicating a suitable location for the control on a paper drier of common type; Fig. 3 is a transverse section taken on the line 3--3 of Fig. l

and showing the bulb of the thermostatic control in contact with the paper web; Fig. 4 is a diagrammatic view of the opposite side of the drier showing the connections for supplying steam and withdrawing condensate; Fig. 5 is a vertical section through the operating mechanism for the stem valve or stock gate; Fig. 6 is a section taken on the line 6-6 of Fig. 5 and Fig. 7 is a diagrammatic illustration showing the location of the stock control gate which is operated by my device.

In the drawings, the numeral 6 indicates the moistpaper web as it approaches the drier from the press section of the paper machine. The drier illustrated is of the type having drying cylinders 7, 8, 9 and 10 around which the paper web passes successively in the usual tortuous path. In Fig. 4 the device is shown as applied to a drier having steam supply and condensate withdrawal connections arranged generally as described and claimed in my Patent No. 1,575,615, dated March 9th, 1926, for a Heating system for paper driers. The driers 7 and 8 at the wet end of the machine constitute a section separate from the driers 9 and 10, being supplied with steam at a constant pressure from a header 11. Condensate withdrawal pipes 12 are provided with check valves 13 for allowing flow to a header 14, which is separate from a header 15 for receiving the condensate from the section represented by the driers 9 and 10. A header 16 has suitable connections for supplying the several driers 9 and 10 with steam and communicating with the header 16 is a supply pipe 17 controlled by a valve 18 through which steam at a higher temperature and pressure than that supplied to the header 11 is furnished. The valve 13 is of the well-known balanced type.

A long bulb 19 for a thermostatic control is located in contact with the paper web 6 at a point on said web between the driers 8 and 9. This bulb 19 extends horizontally the entire width of the web 6 and is supported on arms 20. These bar 21 having pivot bearings at its ends in frame members 22 of the machine. One end of the bar 21 projects from the frame and has a crank 23 secured thereto for moving the bulb 19 to and from its position in contact with the web 6. The bulb 19 is connected by a flexible-tube 24 to suitable indicating and control means responsive to the temperature of the paper web.

As shown in Figs. 1 and 2, the indicating and control apparatus comprises a bellows or expansible chamber 25 having a fixed support 26 at one end and adapted to actuate a lever 27 at its other end. The lever 27 is tiltable on the pin 28 having a vertically adjustable support 29 and its end 30 is arranged to make electrical contact with terminals 31, 32 and 33 for three branch circuits. The signal circuits shown in Fig. 1 comprise a battery 34 having electrical connection through a wire 35 with the lever 30 and having its opposite terminal connected to branch circuits severally including signal lamps 36, 37 and 38. The lamps 36, 37 and 38 are preferably made of different colors so that normal, insuflicient and excessive temperatures at the bulb 19 are shown by visual signals. It will be understood that audible signals, or a suitable recording device, may be substituted for such visual signals. 1

The adjustable support 29 is movable vertically in a tubular member 29, being held against rotation by a key 40. To raise or lower the support 29, a screw 41 is journaled in an insulated base 42 and threaded in a tapped bore of the support 29; A small spring 43 retains one end of the lever 27 in contact with a projection 44 on the expansible chamber 25, said projection having electrical insulating material on its end in contact with the lever 27. To limit movement of the lever 27 and chamber 25, I provide a band 27a fixed on the support for the terminals 31, 32 and 33, above and below said terminals. This band 27a also holds the end of the lever 30 to a path which insures contact with said terminals. I

As shown in Fig. 5, the coil of a solenoid 45 is placed in the circuit including the signal lamp 36, wires 46 and 47 being provided therefor. The wire 47 has a branch 48 (Fig. 1) to include the battery 34 in the circuit. From the central contact 32 a wire 49 extends to connect the wires 47 and 48 and constitute a branch circuit including the signal lamp 37. The coil or a solenoid 50 is placed in series with the lamp 38 by wires 51 and 52, the latter wire connecting with the wire 47.

The steam control valve 18 for the driers 9 and 10 has a long stem 53 supported in suitable bearings 54 and a laterally bent arm on the stem is arranged to be actuated by plungers 55 and 56 of the solenoids 45 and 50 respectively. Coiled tension springs 57 are interposed between the valve stem 53 and the solenoid plungers to transmit movement to the valve stem. Fixed on the solenoid plungers are suitable collars 58 to limit movement in one direction. The solenoids are secured to arms 59 having a common support 60, said arms being independently adjustable along the support 60 and secured thereto by bolts 61 engaging in suitable slots in the support and arms. A large screw 62 is arranged to be turned by a handle 63 to move the support 60 relative to the valve 18 and the support 60 has threaded bearings 64 on the screw 62. Suitable lugs 65 engage in guide grooves 66 in a bracket 67 while the latter is secured by bolts 68 on the frame of the drier adjacent to the steam supply pipe 17.

Mechanism similar to that shown in Figs. 5 and 6 is employed to actuate the stock control gate 70 (Fig. 7). This control gate has an operating rod 71 similar to the rod 53 and is raised and lowered by solenoids similar to the solenoids 45 and 50. In the diagrammatic illustration of Fig. 7, the numeral 72 indicates the usual head box which is supplied with stuff from the machine chest through a pipe 73 communicating with a chamber 74 in the head box. The excess of stock from the chamber 74overfiowsapartition 75 into a chamber 76 whence it returns to the machine chest through an overflow pipe 77. A part of the stock from the chamber 74 passes through an opening 78 in a partition 79 into a third chamber 80. The flow through the opening 78 is controlled by the gate 70 and a pipe 81 carries the stock from the chamber to the Jordan 82. The outlet pipe 83 from the Jordan is supplied with white water from the screens through a pipe 84 and the white water and stock from the Jordan is forced by a pump 85 through a pipe 86 extending to the screens of the Fourdrinier machine, or in the case of a machine of the cylinder type, to the cylinders.

Where both the stock consistency and heat supply for the drier are to be automatically regulated, a pair of solenoids 45 is placed in series with the terminal 31 and a pair like solenoid 50 is arranged in series with the terminal 33. In other respects the mechanism for actuating gate 70 is like that shown in Figs. 5 and 6 for valve 18.

Operation The operation of my device will be descri:ed by reference to a specific example where the temperature of the paper web 6 in degrees Fahrenheit are indicated in Fig. 4. These temperatures are taken from a paper machine having a baby drier 7 of 22-inch diameter and in which the other driers 8, 9 and 10 are 4-feet in diameter. In the illustrated example, steam at a pressure of about two pounds per square inch, gauge, was supplied to the driers 7 and 8 and steam at seven pounds gauge pressure was supplied to the driers 9 and 10, the speed of the paper being approximately 600 feet per minute, constant, and the basis weight of the paper 65 pounds. It was found that the paper web, after passing around the periphery of the drier 9 had reached approximately 170 Fahrenheit and this temperature remained substantially constant at the subsequent driers 10 due to the vaporization of the moisture content in the web.

Thus it will be evident that the driers 7, 8 and 9 progressively raise the temperature and the bulb 19 or thermostatic control element is located on what may be termed the rising portion of the temperautre curve for the machine. A substantially uniform lineal speed of the paper is maintained in the operation of the drier.

It will be understood that the mechanism shown in Fig. 5 as applied to the valve 18, is duplicated where the stock consistency is to be regulated. In the latter case the springs 57 are merely connected to the actuating rod 71 of the gate 70, and where both the steam valve and stock gate are to be actuated automatically, duplicates of solenoids 45 and 50 are placed in series with those for the steam valve.

When the paper machine is started the crank 23 is manipulated to move the bulb 19 out of contact with the paper web. The machine is placed in operation in the usual manner and the consistency and pressure of the steam supplied to the driers is adjusted until the machine is running properly. Now the crank 23 is manipulated to move the temperature element into contact with the sheet. This causes the volatile fill of the bulb '19, or other suitable or well-known substitute, to

actuate the expansible chamber 25 and place the indicator lever 27 in a position which may or may not cause contact with the electric terminal 32 indicating normal operation. To move the lever 27 to the desired normal position the screw 41 is turned in the appropriate direction to bring the end 30 of the lever on the central contact 32 thus illuminating the signal lamp 3'7. When the apparatus has been so adjusted, an excess of moisture in the web 6 as it approaches the drier '7 will be reflected in the form of a reduction in the normal temperature at the point of contact with the bulb 19. This causes a reduction in the fluid pressure in the chamber 25 so that the lever 27 is moved to contact with the terminal 31 thus displaying the signal lamp 36 and energizing the solenoid 45. The plunger 55 of that solenoid is drawn upward, thereby increasing the tension of the spring 57 and actuating rod 53 to increase the opening of the valve 18 (and/ or gate '70) giving an increased heat supply in the secondary group of driers 9 and 10. Where the gate '70 is connected to the solenoids, the stock is thickened when the solenoid 45 is energized. This condition continues until the temperature of the web at the bulb 19 returns to normal or is raised above normal so that the lever 2'7 is removed from the contact 31. When either change occurs, the circuit, including solenoid 45 and lamp 36 is opened and, upon return to normal temperature, the circuit, including the wire 49 and lamp 3'7, is closed.

If the temperature at the bulb 19 is raised above normal the end 30 of the lever 27 completes the circuit by making contact with the terminal 33 and causing the lamp 38 and solenoid 50 to be energized. The plunger 56 is now drawn downward and the valve stem 53 is actuated to reduce the flow through the valve 18 and/or the gate for controlling the stock. Reduced flowof steam to the driers 9 and 10 results in a reduction in the drying and compensation for .the increased temperature at the bulb 19. Where actuating means "for the gate 70 are employed, movement of the gate '10 under the action of the solenoids causes an increase or decrease in the rate of flow of stock from the head box 72 and the corresponding thickening or thinning of the mixed stock and white water flowing to the paper machine from the pipe 86.

The bolts 61 permit independent movement of the supporting arms 59 to afford means for adjusting the tension of the springs 5'7. The handle 63 of the screw 62 is turned to increase or decrease the opening of the valve 18 which is required for normal operation. Thus when the machine is first placed in operation and adjusted to give the normal thickness and moisture content to the paper web the handles 63 at the valve 18 and gate '70 are operated to adjust the supply of steam and opening of the gate 70 and thereby give the normal moisture content and basis weight or stock consistency.

My device may be used without the automatic actuating mechanism for the steam and stock valves by employing the indicators 36, 37 and 38 and manual operation of the valves. In the case of manual operation the wires 46 and 51 are merely connected to the wire 48.

It will be readily understood that this invention may be used advantageously in the drying or treating of fabrics or webs other than paper and the foregoing specification is merely illustrative of one embodiment within the broad scope of the appended claims.

Having described my invention what I claim as new and desire to protect by Letters Patent is:

1. The combination with a machine having drying elements arranged in initial and secondary groups to successively heat a rapidly moving web, of a thermostatic control element in contact with the web and spaced from said drying elements longitudinally of the web between said groups and means responsive to said element for indicating changes in the basis weight.

2. The combination with a machine having drying elements arranged in initial and secondary groups to successively heat a moving web, separate heat supplies for said groups, a thermostatic control element in contact with said web and spaced from said drying elements longitudinally of the web between said groups, means for regulating the heat supply for said secondary group and means responsive to said thermostatic control element to indicate changes in the basis weight of said web.

3. The combination with a paper making machine having cylindrical drying elements arranged in initial and secondary groups to successively heat a moving paper web, separate heat supplies for said groups, a thermostatic control element in contact with said web between said groups and means for regulating the heat supply for said secondary group in response to said thermostatic control element.

4. The combination with a paper making machine having driers arranged in initial and secondary groups near the wet end of said machine to progressively raise the temperature of a moving web, of a thermometer element in contact with said web between said groups of driers, heat supplies for said driers means accessible from a side of said machine for removing said element from the path of said web andmeans under control of said thermometer element for regulating the heat supplied to said secondary group of driers.

5. The combination with a paper machine having rotary, cylindrical driers arranged in initial and secondary groups to progressively raise the temperature of a moving paper web, of control means having a long thermometer bulb extending substantially the entire width of said web, in contact therewith, between said groups of driers andelectrical means under control of said control means for indicating changes in the basis weight of the paper web at said bulb.

6. The method of regulating a drier having drying elements near the wet end of said drier to progressively raise the temperature of a moving web of material to be dried, said elements being ararnged in initial and secondary groups, which consists in maintaining a substantially constant heat supply for said initial group while regulating the heat supplied to said secondary group according to the temperature of the web between said groups and at a point removed longitudinally of the web from said driers.

'7. The combination with a paper machine having rotary, cylindrical driers arranged in initial and secondary groups to progressively raise the temperature of a moving paper web, of contol means having a long thermometer bulb extending substantially the entire width of said web, in contact therewith, between said groups of driers and means for moving said bulb out of. contact with said web.

ARTHUR E. BROUGHTON. 

